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The capability of NASA radar altimeter Topex for land surface studies at regional or global scale is investigated. The analyzed data, available since mid-1992 consist of dual-frequency backscattering coefficients values (Ku and C band) estimated at the nadir pointing angle along the satellite tracks between 66°S and 66°N and averaged in 0.75° ground resolution cell. Mean global backscatter images of the entire land surfaces are presented in Ku, C band and the difference C–Ku. Statistics and major temporal signals over nine entire years are also presented at a global scale. Finally, temporal profiles of backscatters are extracted for main land types (desert, tropical forest, wet and dry savanna, boreal regions, ice sheet) to validate the dataset and to analyze radar response to land surface variability through 9 years. Results indicate the high capabilities of Topex–Poseidon (T–P) radar altimeter data for monitoring …